rt，人眼比较 wa 的点输出似乎一样？///

#include<bits/stdc++.h>
using namespace std;
int n, m; string op, ad;
map <string, int> ss;
bool check(string s){
	int d = 0, m = 0, x = 0; bool f = 0, ff = 0;
	for (int i = 0; i < s.size(); i++){
		if (s[i] == '.') ++d;
		else if (s[i] == ':') ++m;
		if (s[i] >= '0' && s[i] <= '9') {
			x = x * 10 + s[i] - '0';
			if (s[i] != '0') ff = 1;
			if (s[i] == '0' && !ff) f = 1;
		}
		else if (x < 0 || x > 255 || (x != 0 && f)) return 0;
		else f = 0, x = 0, ff = 0;
	}
	if (x < 0 || x > 65535 || (x != 0 && f)) return 0;
	if (m != 1 || d != 3) return 0;
	return 1;
}
int main(){
	ios::sync_with_stdio(0); cin.tie(0);
//	freopen("network3.in", "r", stdin);
//	freopen("qwq.out", "w", stdout);
	cin >> n;
	while (n--){
		cin >> op >> ad; ++m;
		if (!check(ad)){
			cout << "ERR\n";
			continue;
		} 
		if (op[0] == 'S'){
			if (ss[ad] == 0){
				ss[ad] = m;
				cout << "OK\n";
			} else cout << "FALL\n";
		} else{
			if (ss[ad] == 0) cout << "FALL\n";
			else cout << ss[ad] << endl;
		}
	}
	return 0;
}